Hochschule Konstanz University of Applied Sciences
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Key insights from climate communication – and how they can inspire sustainability in higher education
No full textPurpose
In order to combat climate change and safeguard a liveable future we need fundamental and rapid social change. Climate communication can play an important role to nurture the public engagement needed for this change, and higher education for sustainability can learn from climate communication.
Approach
The scientific evidence base on climate communication for effective public engagement is summarised into ten key principles, including ‘basing communication on people’s values’, ‘conscious use of framing’, and ‘turning concern into action’. Based on the author’s perspective and experience in the university context, implications are explored for sustainability in higher education.
Findings
The article provides suggestions for teaching (e.g. complement information with consistent behaviour by the lecturer, integrate local stories, and provide students with basic skills to communicate climate effectively), for research (e.g. make teaching for effective engagement the subject of applied research), for universities’ third mission to contribute to sustainable development
in the society (e.g. provide climate communication trainings to empower local stakeholders), andgreening the campus (develop a proper engagement infrastructure, e.g. by a university storytelling exchange on climate action).
Originality
The article provides an up-to-date overview of climate communication research, which is in itself original. This evidence base holds interesting learnings for institutions of higher education, and the link between climate communication and universities has so far not been explored comprehensively
Erfahrungsbericht zum Fortbildungssemester SS 2023 von Prof. Dr. Christian Wache der HTWG Konstanz
No full textShort-Term Density Forecasting of Low-Voltage Load using Bernstein-Polynomial Normalizing Flows
No full textThe transition to a fully renewable energy grid requires better forecasting of demand at the low-voltage level to increase efficiency and ensure reliable control. However, high fluctuations and increasing electrification cause huge forecast variability, not reflected in traditional point estimates. Probabilistic load forecasts take uncertainties into account and thus allow more informed decision-making for the planning and operation of low-carbon energy systems. We propose an approach for flexible conditional density forecasting of short-term load based on Bernstein polynomial normalizing flows, where a neural network controls the parameters of the flow. In an empirical study with 3639 smart meter customers, our density predictions for 24h-ahead load forecasting compare favorably against Gaussian and Gaussian mixture densities. Furthermore, they outperform a non-parametric approach based on the pinball loss, especially in low-data scenarios
Entwicklung und Analyse eines Turmes aus Buchenfurnierschichtholz für eine Kleinwindkraftanlage
No full textDie Energiepreise in Deutschland steigen und viele Immobilienbesitzer wollen unabhängiger von den Stromerzeugern werden, weshalb sie in eine eigene Stromproduktion investieren. Eine optimale Ergänzung zu einer Photovoltaikanlage stellt dabei eine Kleinwindkraftanlage dar, die im Vergleich zu den großen Anlagen geringere Umweltbelastungen verursacht. Allerdings entstehen beim Bau einer Kleinwindkraftanlage hohe Kosten, weshalb dieses Konzept kaum verbreitet ist.
Die Türme von Windkraftanlagen werden normalerweise aus Stahl hergestellt. Bei der Herstellung dieses Baustoffs werden große Mengen an Treibhausgasen freigesetzt. Ein umweltfreundlicheres Material ist der nachwachsende Rohstoff Holz. Die Herstellung der Türme in Holzbauweise ist bisher kaum zu finden. Daher wird in dieser Arbeit untersucht, ob ein Holzturm eine Alternative zum Stahlturm sein kann und ob dadurch die Investitionskosten für eine Kleinwindkraftanlage gesenkt werden können.
Um die Forschungsfrage zu beantworten, wurde ein Konzept für einen Holzturm aus Buchenfurnierschichtholz entwickelt. Zunächst wurde die Bedeutung von Buchenholz im Bauwesen erarbeitet. Anschließend wurden die Grundlagen für den Bau von Kleinwindkraftanlagen erforscht und die Abmessungen einer fiktiven Anlage festgelegt. Es wurden die relevanten Einwirkungen ermittelt und die Anlage mittels einer Finiten-Elemente-Berechnung untersucht. Zuletzt wurden die Nachweise für die Tragfähigkeit und die Ermüdungssicherheit des Querschnittes und der Verbindungsmittel geführt.
Bei den Untersuchungen der Randbedingungen konnten keine Argumente gefunden werden, die gegen die Verwendung von Holz sprechen. In einigen Punkten wie beispielsweise in der Herstellungs- und Errichtungsphase sind sogar Vorteile gegenüber dem Stahl zu erkennen. Zudem wurde in einer Kostenschätzung herausgefunden, dass ein Holzturm auch preislich mithalten kann und dass die Herstellungskosten sogar gesenkt werden können. Die Gesamtkosten für eine Kleinwindkraftanlage können dennoch nur unwesentlich gesenkt werden. Die Investition ist daher nur sinnvoll, wenn am geplanten Standort genügend Wind zur Verfügung steht und wenn der produzierte Strom größtenteils selbst genutzt werden kann.Energy prices in Germany are rising and many real estate owners wish to become more independent from electricity producers, which is why they are investing in their own electricity production. An optimal complement to a photovoltaic system is a small wind turbine, which causes less environmental impact in comparison to the large systems. However, the construction of a small wind turbine incurs high costs, which is why this concept is rarely widespread.
The towers of wind turbines are normally made of steel. The production of this construction material releases large quantities of greenhouse gases. A more environmentally friendly material is the renewable resource wood. The production of towers with a wooden structure can hardly be found so far. Therefore this thesis investigates whether a wooden tower can be an alternative to the steel tower and whether the investment costs for a small wind turbine can be reduced.
To answer the research question, a concept for a wooden tower made of laminated beech veneer lumber was developed. First, the importance of beech wood in construction was elaborated. Then the basic principles for the construction of small wind turbines were researched and the dimensions of a fictitious turbine were defined. The relevant actions were determined and the structure was examined using finite element calculation. Finally, the verifications for the load-bearing capacity and the fatigue safety of the cross-section and the fasteners were carried out.
When examining the boundary conditions, no arguments could be found that speak against the use of wood. In some points, such as the manufacturing and installation phases, advantages can even be seen over steel. In addition, a cost estimate showed that a wooden tower can also keep up in terms of price, and that manufacturing costs can be reduced. Nevertheless, the total costs for a small wind turbine can only be decreased insignificantly. The investment therefore only makes sense if there is sufficient wind at the planned location and if most of the electricity produced can be used itself
Assessing the Feasibility of Replacing Subjective Questionnaire-Based Sleep Measurement with an Objective Approach Using a Smartwatch
Get PDFIn order to ensure sufficient recovery of the human body and brain, healthy sleep is indispensable. For this purpose, appropriate therapy should be initiated at an early stage in the case of sleep disorders. For some sleep disorders (e.g., insomnia), a sleep diary is essential for diagnosis and therapy monitoring. However, subjective measurement with a sleep diary has several disadvantages, requiring regular action from the user and leading to decreased comfort and potential data loss. To automate sleep monitoring and increase user comfort, one could consider replacing a sleep diary with an automatic measurement, such as a smartwatch, which would not disturb sleep. To obtain accurate results on the evaluation of the possibility of such a replacement, a field study was conducted with a total of 166 overnight recordings, followed by an analysis of the results. In this evaluation, objective sleep measurement with a Samsung Galaxy Watch 4 was compared to a subjective approach with a sleep diary, which is a standard method in sleep medicine. The focus was on comparing four relevant sleep characteristics: falling asleep time, waking up time, total sleep time (TST), and sleep efficiency (SE). After evaluating the results, it was concluded that a smartwatch could replace subjective measurement to determine falling asleep and waking up time, considering some level of inaccuracy. In the case of SE, substitution was also proved to be possible. However, some individual recordings showed a higher discrepancy in results between the two approaches. For its part, the evaluation of the TST measurement currently does not allow us to recommend substituting the measurement method for this sleep parameter. The appropriateness of replacing sleep diary measurement with a smartwatch depends on the acceptable levels of discrepancy. We propose four levels of similarity of results, defining ranges of absolute differences between objective and subjective measurements. By considering the values in the provided table and knowing the required accuracy, it is possible to determine the suitability of substitution in each individual case. The introduction of a “similarity level” parameter increases the adaptability and reusability of study findings in individual practical cases
Current status and prospects of automatic sleep stages scoring: Review
Get PDFThe scoring of sleep stages is one of the essential tasks in sleep analysis. Since a manual procedure requires considerable human and financial resources, and incorporates some subjectivity, an automated approach could result in several advantages. There have been many developments in this area, and in order to provide a comprehensive overview, it is essential to review relevant recent works and summarise the characteristics of the approaches, which is the main aim of this article. To achieve it, we examined articles published between 2018 and 2022 that dealt with the automated scoring of sleep stages. In the final selection for in-depth analysis, 125 articles were included after reviewing a total of 515 publications. The results revealed that automatic scoring demonstrates good quality (with Cohen's kappa up to over 0.80 and accuracy up to over 90%) in analysing EEG/EEG + EOG + EMG signals. At the same time, it should be noted that there has been no breakthrough in the quality of results using these signals in recent years. Systems involving other signals that could potentially be acquired more conveniently for the user (e.g. respiratory, cardiac or movement signals) remain more challenging in the implementation with a high level of reliability but have considerable innovation capability. In general, automatic sleep stage scoring has excellent potential to assist medical professionals while providing an objective assessment
Risikobeschränkung in der Portfoliooptimierung
Get PDFDas Management von Aktienfonds strebt effiziente Mischungen von Aktien an. Nachdem diese durch Optimierungsverfahren ermittelt wurden, müssen sie aus ökonomischen oder rechtlichen Gründen oft angepasst werden mit der Konsequenz, dass die Lösungen nicht mehr effizient sind. Ein rechtlicher Grund kann bei einem öffentlich angebotenen Aktienfond der Artikel 52(2) der EU-Richtlinie 2009/65/EC bzw. das KAGB § 206 sein. Ein Teil der Richtlinie besagt z.B., dass in eine Aktie nie mehr als 10% des Budgets investiert werden kann. Diese Regeln insgesamt sich auch als 5-10-40-Bedingung bekannt. Um derartige Risikobeschränkungen in der Portfoliooptimierung zu integrieren wurden zwei Optimierungsmodelle entwickelt – ein quadratisches und ein lineares. Die Modelle wurden anhand von historischen Renditedaten des HDAX getestet. Das lineare Modell zeigt, dass die Vorgaben der EU-Richtlinie die angestrebte Volatilitätsreduktion erreicht. Diese Risikobeschränkung hat aber einen Preis, der in den Währungen „Renditeverlust“ bzw. „Volatilitätszuwachs“ ausgedrückt werden kann. Bei gleicher Volatilität erzielte das nicht durch die 5-10-40-Bedingung eingeschränkte Portfolio eine ca. 10% höhere Jahresrendite. Der „Volatilitätszuwachs“ ist im Umfeld des minimalen Volatilitätspunktes (MVP) gering, kann aber bis zu 25% betragen, wenn Portfolios die unter der 5-10-40-Bedingung ermittelt wurden verglichen werden mit uneingeschränkt optimierten Portfolios bei jeweils gleicher Rendite. Das quadratische Modell baut auf dem Ansatz von H. Markowitz auf und zeigt einen flexibleren Weg der Risikobegrenzung der zu vergleichbaren Resultaten führt.The management of equity funds tries to find an efficient selection of stocks. After these have been determined by optimization procedures, they often have to be adjusted for economic or legal reasons with the consequence that the solutions are no longer efficient. In the case of a publicly offered equity fund, a legal reason can be Article 52(2) of the Directive 2009/65/EC of the European Parliament and of the Council of 13 July 2009 or the KAGB § 206. A part of the directive states e.g. that never more than 10% of the budget can be invested in one share. These rules in total are also known as the 5-10-40 condition. In order to integrate such risk constraints inportfolio optimization, two optimization models have been developed - a quadratic and a linear one. The models were tested using historical return data from the HDAX. The linear model shows that the specifications of the EU Directive achieve the targeted volatility reduction. However, this risk constraint has a price, which can be expressed in terms of the currencies "return loss" or "volatility gain". For the same volatility, the portfolio not constrained by the 5-10-40 condition achieved an annual return that was approximately 10% higher. The"volatility gain" is small around the minimum volatility point (MVP), but can be as high as 25% when portfolios determined under the 5-10-40 condition are compared to unconstrained optimized portfolios at the same return in each case. The quadratic model is based on the approach of H. Markowitz and shows a more flexible way of risk limitation that leads to comparable results
Wissensmanagement in der Investitionsgüterindustrie
No full textIm Investitionsgüterservice ist Wissen längst zu einem zentralen Erfolgshebel geworden, sowohl zur Steigerung der Prozesseffektivität und -effizienz als auch als Fundament für werthaltige Geschäftsmodelle. Das Management Service-relevanten Wissens ist für kleine und mittelständische Unternehmen der Investitionsgüterindustrie jedoch oftmals eine nicht zu unterschätzende Herausforderung, welche weit über IT-technische Aspekte hinausreicht. In dem vom BMBF sowie vom ESF (ko)finanzierten Projekt „SerWiss“ wurde vor diesem Hintergrund ein umfassender Lösungsansatz entwickelt und bei zwei Projektpartnern aus der Investitionsgüterindustrie prototypisch umgesetzt
Experiment design for Stress data collection while driving in a simulator
No full textThe principal objective of this study is to investigate the impact of perceived stress on traffic and road safety. Therefore, we designed a study that allows the generation and collection of stress-relevant data. Drivers often experience stress due to their perception of lack of control during the driving process. This can lead to an increased likelihood of traffic accidents, driver errors, and traffic violations. To explore this phenomenon, we used the Stress Perceived Questionnaire (PSQ) to evaluate perceived stress levels during driving simulations and the EPQR questionnaire to determine the personality of the driver. With the presented study, participants can categorised based on their emotional stability and personality traits. Wearable devices were utilised to monitor each participant's instantaneous heart rate (HR) due to their non-intrusive and portable nature. The findings of this study deliver an overview of the link between stress and traffic and road safety. These findings can be utilised for future research and implementing strategies to reduce road accidents and promote traffic safety
Aufhebungsvertrag und Arbeitslosengeld I
No full textZahlreiche Arbeitsverhältnisse werden nicht durch Kündigung, sondern durch Aufhebungsvertrag beendet. Anders als bei der Kündigung hat der Betriebsrat hier kein Vetorecht. Für Beschäftigte macht es dennoch Sinn, den Betriebsrat einzuschalten